Hi Marty, Here's the Sudoku that I mentioned in my post earlier today on the 'Daily Sudoku Puzzles' Discussion page. I was able to fill in the first 10 squares but then I came to a complete standstill. I found no way of proceeding using either basic processing or any of the standard advanced techniques (i.e. x-wing, xy-wing, xyz-wing, or URL). Do you see a way to proceed? I spent a long looking after the 1st 10 squares and all that I was able to find was one xyz-wing that eliminated one candidate from one box. Help! I don't see it any way to proceed after the 1st 10 squares!

9 0 4 0 3 0 0 0 5
7 0 0 2 0 0 6 0 0
0 0 0 0 0 5 0 0 0

0 0 3 0 0 1 9 0 6
0 1 0 0 9 0 0 8 0
5 0 9 7 0 0 3 0 0

0 0 0 6 0 0 0 0 0
0 0 2 0 0 8 0 0 7
3 0 0 0 1 0 2 0 9

If you want, I can provide you with the position I that reached but I'm sure that you'll reach it easily enough so I won't bother. As I mentioned in my earlier post today (on the other page), this puzzle was from a recent local newspaper. I have done their puzzles before and none of them have ever been anywhere near this difficult so I suspect that either I'm missing something or they misprinted the puzzle! Thanks, Don.

I found no way of proceeding using either basic processing or any of the standard advanced techniques (i.e. x-wing, xy-wing, xyz-wing, or URL). Do you see a way to proceed? I spent a long looking after the 1st 10 squares and all that I was able to find was one xyz-wing that eliminated one candidate from one box.

Don,

The grids you see posted by Dan and me have taken basics as far as possible. I can find no X-, XY- or XYZ-Wings or helpful URs. Plus I missed the XYZ-Wing that you played. To complete this puzzle, chains will be required, such as the one that Dan posted.

Thanks for the input guys! I guess it's time for me to learn some of the more advanced techniques. I think the newspaper must have misprinted this though because I've never had to use wings or chains or cycles to solve any of their puzzles before. Also, thanks for directing me to the help page for posting grids. I'll be sure to do that from now on. I'm pretty sure the poor girl at work will be glad tomorrow to hear what you said about this being an awful difficult puzzle for a newspaper. Thanks again, Don.